North part of the North Pacific is a major gateway of wind energy into the ocean
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摘要: 风不仅驱动了上层海洋的环流,也是深层海洋运动的主要能量来源。本文主要研究了北太平洋北部的风能输入的季节性分布特征和年际变化趋势,包括风向表面波、表层地转流和表层非地转流的能量输入。基于SODA3数据的结果表明,风能输入门户随季节变化显著,其中黑潮延伸区是冬季门户,副极地流涡是春、秋季门户,大洋东边界则是夏季门户,能量输入强度逐次递减。21世纪以来,秋冬风能输入明显减弱,春季增加,夏季无显著变化。就变化趋势的空间分布而言,向表面波的能量输入由风场主导,而向表层地转流和非地转流的能量输入则由流场主导。这些机械能输入结果对进一步认识该海域的动力机制有重要意义。Abstract: Wind not only drives the surface ocean circulations, but also provides the main source of kinetic energy for deep ocean movements. This study focuses on the wind energy input to the north part of the North Pacific, including wind energy input to surface wave, surface geostrophic currents and surface ageostrophic currents. Results based on SODA3 (2000–2016) data show that there are obvious seasonal wind energy input gateways, which are the Subpolar Gyre for spring and autumn, the Eastern Pacific for summer and the Kuroshio Extension for winter respectively. The winter gateway gains the most wind energy among the four seasonal gateways, which is about 3−5 times higher than others. Since the beginning of the 21st century, wind energy input in winter gateway has weakened significantly, while increased in spring gateway, but has not changed significantly in summer and autumn gateway. For the spatial distribution of the trend in the 17 years, wind energy input to the surface wave is mainly dominated by the wind field, while wind energy input to the surface geostrophic current and ageostrophic current is dominated by the flow field. These mechanical energy input results are important for further understanding the ocean circulations in the North Pacific.
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Key words:
- wind energy input /
- gateway /
- surface wave /
- surface geostrophic current /
- surface ageostrophic current
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表 1 各个季节门户内风能输入与PDO指数以及ENSO指数的相关系数
Tab. 1 Correlation between wind energy input and PDO index and ENSO index in each seasonal gateway
区域 指数 表面波 表层地转流 表层非地转流 春季门户 PDO 0.29 0.26 0.42 ENSO 0.13 0.05 0.21 夏季门户 PDO −0.35 −0.46 −0.39 ENSO −0.33 −0.44 −0.38 秋季门户 PDO 0.39 0.18 0.38 ENSO 0.24 −0.07 0.21 冬季门户 PDO 0.40 0.32 0.40 ENSO 0.15 0.14 0.14 -
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